Reduced Risk: Ovarian Cancer. Combo estrogen/progesterone birth control pills can lower your risk of this type of cancer. The benefit starts within 3 to 6 months after starting the pill. The longer you take it, the lower your risk. Depo-Provera also lowers the risk, especially if you use it for more than 3 years.
Sporangia are the structures that house and create spores in certain organisms. As many of these organisms are non-mobile, they have no choice but to release the spores out into the environment. This allows the spores, which are haploid, the opportunity to germinate and form gametophytes.
The sporangia of the remainder of the true ferns are all remarkably similar. They are thin-walled and dehiscence is caused by a region of cells with thick inner walls and thin outer walls, usually in a ring, called the annulus. The dehiscence occurs in a specialized region called the stomium.